Subacute zinc deficiency in children with recurrent upper respiratory tract infection.

Serum, urine and hair zinc levels in 20 patients with recurrent upper respiratory tract infection are compared with those of age- and sex-matched controls. Lower hair zinc (1.44 vs 2.00 mmol/g hair, P = 0.004) and higher urinary zinc levels (2.2 vs 1.6 mmol/mol creatinine, P = 0.05) were found, but no difference in serum zinc. The patients had lower-normal height for age (SD-score 0.2 vs 0.7, P = 0.031), there was no difference in weight for height. No correlation was found between the zinc values and the duration of the complaints.